If you are like me, I am hor­ri­ble at knife sharp­en­ing, and get­ting the edge I am look­ing for on a blade.  It takes me for­ev­er to get the right angle stroke, etc to put an edge on a knife.  Any knife for that mat­ter.

WARNING:  This was pre­vi­ous­ly pub­lished else­where, and is a VERY long post.  Please review the con­tents at the top and maybe skip to the area of most inter­est.

I found this online today, and want­ed to share so here it is:Author: Joe Tal­madge
Last Updat­ed: May 1998
Changes: Added a para­graph on the impor­tance of com­plete­ly remov­ing the burr

This FAQ has been improved immea­sur­ably through the tests and dis­cus­sions on rec. knives. I thank every­one who has engaged in sharp­en­ing debates over the years, I’ve grabbed ideas here and there from many of you.


I. Intro­duc­tion
II. The Fun­da­men­tals of Sharp­en­ing
— Get­ting a sharp edge
— What angle?
— What kind of stone?
— Should I use oil or water on my stone?
— How fine should my stone be? Impor­tant notes on grits!
— Strop­ping
— Using a steel

III. Putting it all togeth­er
— Free­hand tips and tricks
— Why does my knife go dull so fast?
— Putting it all togeth­er

IV. Sharp­en­ing The “Dif­fer­ent­ly-Ground” Blade
— Those pesky ser­rat­ed blades
— The Moran (Con­vex) edge
— The chis­el-ground edge

V. Overview of var­i­ous sharp­en­ing sys­tems
— Clamp-on sharp­en­ing guides (Razor Edge, Buck, etc.)
— Clamp-and-Rod rigs (Lan­sky, Frost, etc.)
— V‑type sharp­en­ers (Spy­der­co Tri­an­gle, etc.)
— Oth­er mis­cel­la­neous
— Free­hand sharp­en­ing, and its won­drous advan­tages!

I. Introduction

When I start­ed writ­ing this FAQ, I began by writ­ing a detailed trea­tise on how to sharp­en. I soon found that there was no way I could do this in the kind of detail I want­ed with­out end­ing up with a book-length FAQ. As it turns out, some­one has already writ­ten a book on sharp­en­ing and done a bet­ter job than I could have done. So the most impor­tant part of this FAQ, for the begin­ner, is the fol­low­ing rec­om­men­da­tion: the first thing you need to do is buy and read The Razor Edge Book of Sharp­en­ing by John Juran­itch. No mat­ter what sharp­en­ing sys­tem you end up using, the fun­da­men­tals as laid out by Juran­itch remain intact. I don’t agree with Juran­itch on every­thing, but the illus­tra­tions he gives real­ly help with under­stand­ing the prin­ci­ples.

So this FAQ will dis­cuss the cen­tral ele­ments of sharp­en­ing, and then go on to more detailed sub­jects. Sharp­en­ing angles, hones, sharp­en­ing sys­tems, the lat­est fads in edges (e.g., chis­el grinds), etc. Basi­cal­ly, Juran­itch will show you how to get a burr and grind it off to end up with a sharp knife. Hope­ful­ly, the FAQ will tell you every­thing else.

For many peo­ple, when they try to sharp­en a knife, the knife actu­al­ly gets duller! If it’s any con­so­la­tion, I was in the same boat at one time. The best way to start out is to read about the sharp­en­ing fun­da­men­tals, and then use some kind of sharp­en­ing sys­tem (dis­cussed below) that pre-sets the angles. That way, you can begin by learn­ing how to raise a burr, feel for the burr, and then grind it away, with­out hav­ing to wor­ry about keep­ing the angle con­sis­tent as well.
When you under­stand how to sharp­en, then you can get rid of the rig, buy some flat hones, and learn how to sharp­en free­hand.

II. The Fundamentals of Sharpening

- Getting a Sharp Edge

Okay, I lied about not dis­cussing the sharp­en­ing rit­u­al itself. Here’s a much-too-short review of the sharp­en­ing process, before we get into the rest of the FAQ. If this sec­tion is con­fus­ing, read _The Razor Edge Book of Sharpening_. Many of the sub­jects in this sec­tion (e.g., stone grits) are explored fur­ther else­where in the FAQ.

You grind one edge along the stone edge-first until a burr (aka “wire”) is formed on the oth­er side of the edge. You can feel the burr with your thumb, on the side of the edge oppo­site the stone. The pres­ence of the burr means that the steel is thin enough at the top that it is fold­ing over slight­ly because the bev­el you’ve just ground has reached the edge tip. If you stop before the burr is formed, then you have not ground all the way to the edge tip, and your knife will
not be as sharp as it should be. The form­ing of the burr is crit­i­cal­ly impor­tant — it is the only way to know for sure that you have sharp­ened far enough on that side. Once the burr is formed on one side, turn the knife over and repeat the process.

To re-cap, you’ve sharp­ened one side only until you felt a burr along the entire length of the oppo­site side, then you switched sides and repeat­ed the process. I sug­gest you do not fol­low the direc­tions that come with many sharp­en­ers, of the form “Do 20 strokes on one side, then 20 strokes on the oth­er”. You go one side only until the burr is formed; if that takes 10 strokes or 50 strokes, you keep going until you get a burr, peri­od. Only then do you flip the knife over and do the oth­er side.

Hav­ing raised a burr, our job now is to progress to fin­er stones, in order to make the edge smoother and remove the burr. So now we run the blade along the stone from end to tip, this time alter­nat­ing sides with each stroke. Switch to a fin­er stone, and then do it again.

Remem­ber, now that we’ve gone through all this trou­ble to raise the burr, our top objec­tive now is to com­plete­ly remove the burr. Per­haps the best way to accom­plish this is by dou­ble-grind­ing. That is, when you are done sharp­en­ing, raise the angle a cou­ple of degrees, and take one or two very light strokes across the stone. This will typ­i­cal­ly remove the burr com­plete­ly. Also remem­ber that dif­fer­ent steels and dif­fer­ent heat treats can affect the burr, both its orig­i­nal size and how easy it is to grind it off. Some steels just don’t want to let go of their burr, pre­fer­ring instead to let it flip flop from side to side — you will have to be espe­cial­ly vig­i­lant to make sure you’ve ground the burr back off with these steels. Dou­ble grind it!

Some­times, the burr is turned direct­ly down­wards dur­ing sharp­en­ing, and since it is very thin and razor-sharp, it seems like an incred­i­ble edge. This is called a “wire edge”. But being frag­ile, it will break off the very first time you use the knife, leav­ing you with an extreme­ly dull knife. If you seem to be get­ting good sharp­en­ing results on your knives, but they are get­ting dull very quick­ly with lit­tle use, you may be end­ing up with a wire edge. If that’s the case, you’ll need to be care­ful and watch out specif­i­cal­ly for a wire edge; you should try pro­gress­ing down to fin­er stones, try dou­ble-grind­ing the edge, and give the knife a quick strop­ping once you’re fin­ished (all these terms are explained below). If your knife is fad­ing fast as you’re sure it’s not because you left a wire edge,
steel­ing between uses may be what you need. My last few strokes on the stone become pro­gres­sive­ly lighter, to avoid col­laps­ing the edge and rais­ing anoth­er burr.

On a bad­ly worn or dam­aged edge, I’ll typ­i­cal­ly start with a medi­um (300–400 grit) stone, then move to a fine (600 grit) stone, and then some­times I’ll fin­ish on an extra-fine (1200 grit) stone if I want a more pol­ished edge. How­ev­er, once my knife is sharp I try to re-sharp­en before it gets too worn down. In that case, I can usu­al­ly start on the fine stone. But be sure to read the impor­tant notes on grits lat­er in the FAQ.

Lastly, I may use a leather strop on the knife.

On oth­er sharp­en­ing sys­tems, the same fun­da­men­tals as laid out above still apply. For exam­ple, on a V‑type sharp­en­er, I’ll start by sharp­en­ing one side only against the right-hand stick until a burr forms. Then I switch to the oth­er stick until a burr forms. Only after I’ve raised a burr from both sides will I fol­low the
man­u­fac­tur­er’s direc­tions and alter­nate from one stick to the oth­er between strokes.

- What Angle?

The small­er the angle, the sharp­er your knife will feel. But the small­er the angle, the less met­al that’s behind the edge, and thus the weak­er the edge. So your sharp­en­ing angle will depend on your usage. A sur­geon’s blade will have a very thin, very low-angle edge. Your axe will have a strong, thick, high-angle edge.

Some­thing like a razor blade will hav­ing an angle of around 12- degrees, and it’s chis­el-ground so that’s 12-degrees total. Util­i­ty knives will have angles any­where between 15- and 24- degrees (30–48 degrees total). An axe will have some­thing around a 30-degree angle.

For dou­ble-ground util­i­ty knives, a pri­ma­ry edge of 15–18-degrees, fol­lowed by a sec­ondary grind of 21ish-degrees, works well. Don’t be obsessed with get­ting the exact right angle; rather, make sure that at what­ev­er angle you’ve cho­sen, con­cen­trate on hold­ing it pre­cise­ly.

See also the sec­tions on con­vex edges and chis­el-ground edges.

- What Kind of Stone?

Basi­cal­ly, a stone needs to cut the met­al off the edge. The stones below do this well, and for most of us our time would be bet­ter spent actu­al­ly learn­ing how to sharp­en than wor­ry­ing too much about the minor advan­tages of one stone vs. anoth­er. Get the biggest stones you can afford and have room for. Big stones make the job much much eas­i­er.

The time-hon­ored stone is the Arkansas stone. Soft Arkansas stones pro­vide the coars­er grits, with hard­er stones pro­vid­ing fin­er grits. Many peo­ple use oil on these stones, osten­si­bly to float the steel par­ti­cles and keep them from clog­ging the stone. John Juran­itch has pop­u­lar­ized the notion that oil should absolute­ly not be used when sharp­en­ing, and indeed results from peo­ple using Arkansas stones with­out oil have been very pos­i­tive. How­ev­er, if you have ever used oil on your Arkansas

stone, you need to con­tin­ue using it, or it will clog. If you nev­er put oil on your Arkansas stone, you will nev­er need to.

Syn­thet­ic stones are very hard, and won’t wear like nat­ur­al stones (a nat­ur­al stone may get a val­ley scooped out of it over time). They clean well with deter­gent-charged steel wool, I use SOS deter­gent pads, they clean very very fast and very well. I know you’re think­ing that clean­ing with steel wool will cause the stone to shear off the steel wool and fill up the stone even worse! But I assure you that is not the case, for what­ev­er rea­son SOS pads clean syn­thet­ic stones, they do not make the stones dirt­i­er. Spy­der­co and Lan­sky are some man­u­fac­tur­ers who sell syn­thet­ic stones.

Stones with dia­mond dust embed­ded in them cut aggres­sive­ly. You can remove met­al very quick­ly if you need to, but be care­ful lest you remove too much too fast! DMT, Eze-Lap, and Lan­sky are some man­u­fac­tur­ers who sell dia­mond-based hones. Some dia­mond stones have the prob­lem that the dia­mond dust wears off quick­ly, leav­ing you with a use­less stone. I have expe­ri­ence with the DMT stones, and can say that they do not have this prob­lem.

Japan­ese water stones come in some very high grits — I’ve seen all the way up to 8000! These stones are very expen­sive. The stones sit in a water bath, and a slush forms on top that helps the final pol­ish. Don’t know any man­u­fac­tur­ers, but Bob Eng­nath and Goril­la & Sons both sell Japan­ese water stones.

Both Japan­ese water stones and nat­ur­al stones will even­tu­al­ly dish out in the cen­ter with use. To flat­ten them back out, put some sand­pa­per on a flat sur­face and rub the stone top on it. Wet/dry 400 grit sand­pa­per mount­ed on a table top or glass is reput­ed to work well.

- Should I Use Water or Oil on My Stone

John Juran­itch has pop­u­lar­ized the notion that no liq­uid should be used on the sharp­en­ing stone. Since oil has been used for many years on stones, this leads to some con­fu­sion.

Basi­cal­ly, the pur­pose of the stone is to rub against the blade and remove met­al. Slip­pery liq­uids, like water and espe­cial­ly oil, make the rub­bing slick­er, caus­ing less met­al to be removed, caus­ing sharp­en­ing to take longer. On top of that, Juran­itch claims that as your edge is being sharp­ened on the stone, the oil-sus­pend­ed met­al par­ti­cles are wash­ing over the edge and dulling it again.

On an Arkansas stone, the oil is sup­pos­ed­ly need­ed to float met­al par­ti­cles away from the stone sur­face, lest the stone clog and stop cut­ting. Some peo­ple in this group have used their Arkansas stones with­out oil or water, and have report­ed good results. How­ev­er, if you’ve already used oil on your Arkansas stone, you’ll prob­a­bly need to keep using oil for­ev­er on it, because an already-oiled stone will clog up if not kept oiled. If you have a fresh Arkansas stone, go
ahead and use it with­out the oil, and things should be okay.

I’ve used dia­mond and syn­thet­ic stones with­out liq­uid, and they worked just fine.

Japan­ese water stones are the one type of stone that needs water. The stones are designed to work with water, and as you sharp­en a small amount of the stone’s mate­r­i­al breaks off and forms an abra­sive slur­ry along the top.

In any case, the bot­tom line is: use liq­uid or don’t. Using the liq­uid will make the sharp­en­ing process slow­er and messier, but if you insist on using liq­uid and are will­ing to spend more time, that’s your call. If you don’t have the skill to hold a con­sis­tent angle, it’s all moot any­way!

- How Fine Should My Stone Be? Important notes on grits!

The fin­er the stone, the more pol­ished your edge will become. The rougher the stone, the more the scratch­es in the edge func­tion as “micro-ser­ra­tions” (see also the ser­rat­ed vs. plain edge FAQ). Though the actu­al onto­log­i­cal sta­tus of the micro-ser­ra­tions is debat­able (Juran­itch says there’s no such thing, hav­ing looked under a micro­scope), the ser­rat­ed effect of the coars­er grind is undoubt­ed­ly there.

The more pol­ished the edge, the bet­ter your edge will work for doing push-cut appli­ca­tions like shav­ing, whit­tling, peel­ing an apple, skin­ning a deer. Also, your cut will be more clean and pre­cise with the pol­ished edge.

A rougher, more micro-ser­rat­ed edge will work bet­ter for slic­ing-type appli­ca­tions like cut­ting through coarse rope, wood, etc. The ser­ra­tions present more edge sur­face area and tend to “bite” into the thing being cut.

It is pos­si­ble to get an edge that will shave hair with a medi­um (300–400 grit) stone, with prac­tice [I specif­i­cal­ly men­tion stone grits because many man­u­fac­tur­ers call the 300–400 grit stones “coarse” rather than “medi­um”]. The medi­um stone will have pret­ty big micro-ser­ra­tions. In a pre­vi­ous ver­sion of the FAQ I stat­ed that I find this too rough a fin­ish for my gen­er­al util­i­ty edge. How­ev­er, I’ve since found this to be a real­ly nice edge fin­ish for util­i­ty work –
it won’t shave great, but it does a real­ly nice job of cut­ting coarse mate­ri­als.

Any­one should be able to get an edge that shaves hair eas­i­ly with a fine (600 grit) stone. I find this to be a pret­ty use­ful fin­ish­ing stone, leav­ing enough micro-ser­ra­tions for gen­er­al util­i­ty work but still being hair-shav­ing sharp.

An extra fine stone (1200 grit) should start pol­ish­ing the edge, and you should end up with a hair-pop­ping sharp edge. This is also a good choice for a gen­er­al util­i­ty fin­ish, espe­cial­ly on a par­tial­ly-ser­rat­ed blade, where the ser­ra­tions can be used when the slight­ly-pol­ished main part of the blade becomes less effec­tive.

One can buy Japan­ese water stones with grits up to 8000, which leaves a pol­ished edge that’s so sharp, your hairs will jump off your arm when they see the edge com­ing. I would ques­tion this fin­ish on an every­day util­i­ty knife which might be called upon to cut through a thick rope or what have you, but it is a fin­ish that works well when a pol­ished edge is called for.

************* IMPORTANT TIP ****************

Many trea­tis­es on sharp­en­ing tend to focus on get­ting a pol­ished, razor-like edge. This is par­tial­ly the fault of the tests we use to see how good our sharp­en­ing skills are. Shav­ing hair off your arm, or cut­ting a thin slice out of a hang­ing piece of news­pa­per, both favor a razor-pol­ished edge. An edge ground with a coars­er grit won’t feel as sharp but will out­per­form the razor-pol­ished edge on slic­ing type cuts, some­times sig­nif­i­cant­ly. If most of your work involves slic­ing cuts (cut­ting rope, etc.) you should strong­ly con­sid­er back­ing off to the coars­er stones, or even a file. This may be one of the most
impor­tant deci­sions you make — prob­a­bly more impor­tant than find­ing the per­fect sharp­en­ing sys­tem!

Recent­ly, Mike Swaim (a con­trib­u­tor to rec. knives) has been run­ning and doc­u­ment­ing a num­ber of knife tests. Mike’s tests indi­cate that for cer­tain uses, a coarse-ground blade will sig­nif­i­cant­ly out­per­form a razor pol­ished blade. In fact, a razor pol­ished blade that does extreme­ly poor­ly in Mike’s tests will some­times per­form with the very best knives when re-sharp­ened using a coars­er grind. Mike’s coarse grind was done on a file, so it is very coarse, but he’s since begun favor­ing very coarse stones over files.

The tests seem to indi­cate that you should think care­ful­ly about your grit strat­e­gy. If you know you have one par­tic­u­lar usage that you do often, it’s worth a few min­utes of your time to test out whether or not a dull-feel­ing 300-grit sharp­ened knife will out­per­form your razor-edged 1200-grit sharp­ened knife. The 300-grit knife may not shave hair well, but if you need it to cut the rope, it may be just the tick­et!

If you ever hear the sug­ges­tion that your knife may be “too sharp”, mov­ing to a coars­er grit is what is being sug­gest­ed. A “too sharp” — or more accu­rate­ly, “too fine­ly pol­ished” — edge may shave hair well, but not do your par­tic­u­lar job well. Even with a coarse grit, your knife needs to be sharp, in the sense that the edge bevels need to meet con­sis­tent­ly.

- Stropping

Strop­ping con­sists of run­ning the edge along a piece of leather charged with some kind of abra­sive like strop­ping paste or green chromi­um oxide (I had pre­vi­ous­ly said jew­el­er’s rouge is okay, but have since heard that a more aggres­sive cut­ter is need­ed). It is done for a short time to fin­ish off the burr, or for a long time to give the edge a final pol­ish. Strop­ping is an easy-to-use fin­ish­ing step (as opposed to the dif­fi­cul­ty in keep­ing a con­sis­tent angle on a

Before you strop, remem­ber to wash and dry your new­ly-sharp­ened knife. If you don’t, you might grind left­over met­al par­ti­cles into the strop itself. If you need to charge your strop, put a lit­tle paste on your fin­gers and rub it into the leather. To strop, you run the edge along with the leather with the blade posi­tioned spine first and the edge trail­ing (oppo­site way from sharp­en­ing on a stone). With a thin straight razor, the spine of the razor is always kept on the strop, and direc­tion is switched by flip­ping the razor over along its spine. In my expe­ri­ence, this isn’t nec­es­sary with a util­i­ty knife. You can strop with the blade spine raised above the leather (don’t lift too high — if the edge bites into the leather, that’s too high), and change direc­tions by lift­ing the entire knife
up, turn­ing it over, and plac­ing it back down.

If you’ve nev­er stropped your knife before, give it a try. It will come out very sharp, but of course, pol­ished and so opti­mized for push-type shav­ing cuts. The strop to some extent can make up for a less-than-per­fect sharp­en­ing tech­nique — a sharp knife can be made extra sharp on the easy-to-use strop. How­ev­er, I always tell peo­ple that they should be able to get their knife scary sharp with­out the strop; don’t let the strop keep you from rec­og­niz­ing weak­ness­es and
improv­ing your tech­nique on the hone!

In the absence of a strop (say, out in the field), many peo­ple use their jeans and then their palm as a strop. There’s prob­a­bly no need to point out the dan­ger in this prac­tice, so don’t do it. That said, I must admit to hav­ing done this myself on numer­ous occa­sions, and hav­ing got­ten good results.

A safer and more effec­tive trick is to use card­board (say, the card­board back of a stan­dard notepad). You can option­al­ly charge the card­board with met­al pol­ish, just rub it in with your fin­gers. Then strop as above. Even with­out the pol­ish, the card­board will strop accept­ably. Strop­ping with card­board has become a de-fac­to stan­dard last step for sharp­en­ing chis­el-ground (sin­gle-side ground) knives these days, for burr removal pur­pos­es.

- Using a Steel

The sharp­en­ing steel should be an impor­tant part of your knife main­te­nance strat­e­gy and is maybe the most mis­un­der­stood part.

When you use a knife for a while, espe­cial­ly a knife with a soft, thin edge like that found on a kitchen knife, the edge tends to turn a bit and come out of align­ment. Note that the edge is still rea­son­ably sharp, but it won’t feel or act very sharp because the edge may not point straight down any­more! At this point, many peo­ple sharp­en their knives, but sharp­en­ing is not nec­es­sary and of course, decreas­es the life of the knife as you sharp­en the knife away. It’s also akin to putting in a thumb­tack with a sledge­ham­mer.

The steel is used to re-align the edge on the knife. Read that last sen­tence again. Re-align­ing the edge is all the steel needs to do. It does not need to remove any met­al. Since the steel’s only func­tion is to re-align, the sharp­en­ing steel can be per­fect­ly smooth and still do its job. You’ll see many bumpy steels on the mar­ket, but this is almost cer­tain­ly because con­sumers think that steels must have bumps to work. The bumps can actu­al­ly mess up the edge, and make the work of steel­ing more dif­fi­cult.

There are two schools of thought on steel. Some peo­ple use grooved steels, which align the edge more aggres­sive­ly but are hard­er on the edge. I use smooth steel, which is easy on the edge but may align the edge more slow­ly.

To use the steel, run the knife along with the steel on one side using light pres­sure — no more pres­sure than the actu­al weight of the knife is required! Then switch to the oth­er side and do it again. Repeat a num­ber of times until your edge feels sharp and nice again. I hold the steel in my left hand, the blade in my right, and light­ly run the blade along with the steel while keep­ing the steel sta­tion­ary, but it’s per­fect­ly fine to move both steel and knife past each oth­er at the same time, or what­ev­er works for you.

Most peo­ple run the knife down the steel edge first, the same direc­tion you use when sharp­en­ing. This yields good results. How­ev­er, the­o­ret­i­cal­ly going edge-first along the steel could bite into the edge while straight­en­ing it, and so many peo­ple like to go spine-first (like when strop­ping) instead. This method also works well, and I per­son­al­ly have begun to feel that steel­ing in this direc­tion gets my edge the tini­est bit sharp­er. It is more awk­ward to go spine-first, so if you have any trou­ble with it switch to edge-first, and your edge will end up just fine.

If you steel your knife every time you use it, you will sig­nif­i­cant­ly length­en the time between sharp­en­ings. I’ve found “steel­ing” to be crit­i­cal on kitchen knives, but it’s an incred­i­ble help even on ultra-hard ATS-34.

III. Putting it all together

- Some tips and tricks

If you want to deter­mine if you are sharp­en­ing at the same angle that the blade already has, try this easy trick. Mark the edge bev­el with a mag­ic mark­er. Then go ahead and do a stroke or two on the stone (or take a stroke with your Lan­sky, or what­ev­er). Now pick the knife up and look at the edge. If you have matched the edge angle exact­ly, the mag­ic mark­er will be scraped off along the entire edge bev­el. If your angle is too high, only the mark­er near the very very tip will be gone. If your angle is too low, only the mark­er near where the edge bev­el meets the pri­ma­ry bev­el will be gone.

Anoth­er trick is to use light and shad­ow to get the edge pre­cise­ly. Using strong direct­ly light, lay the edge down on the stone and watch the shad­ow below. As you tilt the spine up, the edge con­tacts more of the stone and the shad­ow dis­ap­pears. As the shad­ow just dis­ap­pears and the edge just touch­es the stone, that’s your angle. If you go high­er than that, you should be able to see the edge tilt­ing over onto the stone.

One trick to free­hand sharp­en­ing is to use your thumb as a guide. I’ll place the spine of the blade against my thumb pad, and rest my thumb on the stone. That way, I can feel the angle between the knife and stone, and make sure that it is con­sis­tent. Typ­i­cal­ly, the hard­est part to free­hand sharp­en is the curv­ing bel­ly of the blade, as keep­ing a con­sis­tent angle here is more dif­fi­cult.

I use all these tricks exten­sive­ly when sharp­en­ing free­hand, and use the mark­er trick even when I’m using a sharp­en­ing rig.

One thing to keep in mind is that there’s no rea­son you need to keep the fac­to­ry edge. If you’re hap­py with that edge, great. How­ev­er, many fac­to­ry edges are too thick to real­ly cut well. If you’re unhap­py with the cut­ting abil­i­ty of your knife, don’t be afraid to try low­er­ing the angle a bit.

- Why does my knife go dull so fast?

A fre­quent com­plaint I hear is, “I sharp­ened my knife and did a good job, it was real­ly sharp. But then after just a few uses it went dull.” Why does this hap­pen?

One of the fol­low­ing fac­tors — and many times a com­bi­na­tion of those fac­tors — is at play:

1. Wire edge

If the burr is not prop­er­ly ground off, but is instead turned down­wards, your knife will feel razor sharp. How­ev­er, the burr quick­ly turns or snaps off, leav­ing you with a very dull-feel­ing knife. Be sure to use a light touch at the end of the sharp­en­ing process and make sure the burr is gone.

2. Thin, weak edge

If the bev­el angle you chose for your knife is too thin for your usage, the edge can chip and get real­ly wavy. Try using a larg­er edge angle, or at least dou­ble-grind­ing the edge.

3. Edge turning

In reg­u­lar use, all edges turn to some extent. If your edge is much too thin, it will be dam­aged as above in #2. If it’s only slight­ly too thin, it will quick­ly turn out. As long as the edge is not being dam­aged, but sim­ply turn­ing, you don’t nec­es­sar­i­ly need to re-grind a thick­er edge. Instead, see if fre­quent steel­ing will give you the per­for­mance you need, it can real­ly work won­ders. Keep in mind it’s dif­fi­cult to see a turned-out edge by eye­ball — only using the steel will tell you con­clu­sive­ly if this is your prob­lem.

4. Thick edge

A thin edge will feel sharp­er than a thick edge. If your edge is too thick, when it starts to dull even the slight­est bit it may no longer feel so sharp any­more. Con­sid­er using a low­er angle and see­ing if that helps. Of course, your thin­ner edge will be more frag­ile than the thick­er edge, so you may end up chip­ping the edge out, and the thin­ner edge may not be fea­si­ble. I per­son­al­ly feel that this is rarely the real prob­lem, so be sure to try the oth­er solu­tions first.

5. Soft steel

Occa­sion­al­ly, a man­u­fac­tur­er or mak­er will make a mis­take while heat treat­ing and the steel in the blade will end up too soft. No mat­ter how well you sharp­en, your blade will still go dull quick­ly. Often, soft steel is the first thing peo­ple point at when their edges dull quick­er than expect­ed. But this prob­lem
real­ly is rel­a­tive­ly rare; in the vast major­i­ty of cas­es, it is one of the above rea­sons rather than soft steel that’s the prob­lem. So if your edge dulls too fast, don’t blame the steel until you’ve exhaust­ed the above options. If it’s still dulling quick­ly, con­tact the man­u­fac­tur­er, they are often inter­est­ed in test­ing to see if they made a mis­take.

- Putting it all together

As you use your knives, you may see your sharp­en­ing strate­gies change. Many of us seem to be hom­ing in on the phi­los­o­phy that you should choose the thinnest, coars­est edge pos­si­ble that can do your job with­out the edge being dam­aged, espe­cial­ly in the con­text of gen­er­al usage.

Thin blades and low-angle edges seem to cut bet­ter than thick ones. They slide through the mate­r­i­al being cut with less effort. This makes sense — the wider the V that your edge forms, the more met­al you’re push­ing into the mate­r­i­al. How­ev­er, go too thin and your edge can chip out. So go as thin as you can with­out dam­ag­ing your edge, and use a steel often to touch it up. Obvi­ous­ly, what “thin” means depends on usage. “Thin” means one thing when the job is slic­ing soft mate­ri­als, some­thing else entire­ly when chop­ping hard mate­ri­als. Light­ly dou­ble-grind­ing a shal­low­er bev­el on a thin edge may help give you the best of both worlds. If your first bev­el is a thin 15-degrees (say), try doing a few light fin­ish­ing strokes at a stouter 24-degress.

Coars­er edges slice bet­ter than pol­ished ones, but a pol­ished edge will lat­er­al­ly push-cut (e.g., shave) bet­ter. If you find your­self doing a lot of lat­er­al push cuts, then you’ll obvi­ous­ly want to pol­ish your edge more. How­ev­er, most peo­ple do much more slic­ing than push cut­ting, and as a result end up with a much more pol­ished edge than opti­mal. You should play around with coars­er grits. The edge won’t do as well shav­ing hair, but unless this par­tic­u­lar knife is a razor blade, who cares? You may find the knife cut­ting through oth­er mate­ri­als much bet­ter than usu­al.

Last­ly, I have become some­thing of a steel fanat­ic. Steel­ing your knife fre­quent­ly — even if the blade is of real­ly high-hard­ness steel — works won­ders on the edge. It also allows you to have a slight­ly thin­ner (and hence bet­ter-cut­ting) edge, because if you steel fre­quent­ly you’ll keep the edge aligned. If you don’t steel at all, you’ll have to use an edge that’s thick enough not to turn, and that may neg­a­tive­ly affect sharp­ness and cut­ting pow­er. Remem­ber to steel
fre­quent­ly, because if your edge’s shape gets too bad, the steel won’t work and you’ll have to go back and sharp­en.

IV. Sharpening The “Differently-Ground” Blade

- Those Pesky Serrated Blades

It is not that dif­fi­cult to sharp­en the Spy­der­co-type ser­ra­tions or the typ­i­cal ser­ra­tions on a bread knife. Both the Lan­sky rig and Spy­der­co’s Tri­an­gle-Angle Sharp­mak­er have spe­cial hones meant to sharp­en ser­rat­ed blades. A tri­an­gle-shaped hone rides along the grooves. Although I can’t quite get my ser­rat­ed knives as sharp as they come from Spy­der­co’s fac­to­ry, I do get them extreme­ly sharp, and am sat­is­fied with the results. Don’t let fear of sharp­en­ing scare you away from ser­rat­ed blades.

I have not tried it, but the above sys­tems sup­pos­ed­ly work for Bench­made-type reverse ser­ra­tions. Cold Steel’s tighter ser­ra­tions would seem to present more of a prob­lem. Cold Steel sells Spy­der­co’s Tri-angle Sharp­mak­er as the solu­tion to sharp­en their ser­ra­tions, so this would seem the log­i­cal sys­tem to try.

Oth­ers claim to get excel­lent results from the tapered dia­mond-coat­ed rods that are being sold to sharp­en ser­rat­ed knives. The dis­ad­van­tage of these is that you have to sharp­en each ser­ra­tion sep­a­rate­ly.

For those curi­ous about how a cus­tom mak­er might ser­rate an edge, here’s a quote from A.T. Barr:

When I make a ser­rat­ed blade, I first grind the cut­ting edge down to approx­i­mate­ly .020. I then use two files. A 1/8″ round file and a 3/16″ chain saw file. I then use a course DMT dia­mond rod that is tapered from about 1/16″ to 1/4″. I use that to put the final edge on before heat treat­ing. After heat treat­ing, I again use the same DMT rod to clean up the scale. I put the blade (if a fold­er) or wrap the han­dle (if a sheath knife) in a vise in a hor­i­zon­tal posi­tion. You’re
right, it is not easy, but you can do it.

- The Moran (Convex) Edge

Named after Bill Moran and fea­tured on many of Black­jack­’s knives, the Moran edge (aka con­vex edge) is, well, con­vex. Usu­al­ly, an edge is a straight bev­el over the last mil­lime­ter or two of the knife. With a con­vex edge, the edge con­tin­u­ous­ly curves towards the very point. The advan­tage is that there’s more met­al behind the edge, so you end up with a very sharp but strong edge, which needs to be felt to be believed. Knife­mak­ers typ­i­cal­ly cre­ate this edge with a slack belt, which leads us to the dis­ad­van­tage: if you don’t have a slack belt grinder and the know-how, you’ll need to return your knife to the mak­er for sharp­en­ing peri­od­i­cal­ly.

If you buy an unfin­ished tan­to blade from Bob Eng­nath, you’ll see that edge con­sists of 3 dis­tinct straight grinds, each more acute than the one before. When hand-fin­ish­ing the tan­to, the junc­tures between the grind angles dis­ap­pear, and you end up with a con­vex edge.

Some peo­ple sim­u­late a con­vex edge by dou­ble- or triple-grind­ing the edge. That is, after they’ve ground the edge, they change the bev­el angle and grind a bit more. This is easy to do with Lan­sky-type rigs and the Razor Edge-type clamps. It results in a superb edge. But it is not quite the same thing as a con­vex edge.

Some peo­ple use the term “rolled edge” to mean a con­vex edge. As such, a “rolled edge” is a good thing. But most peo­ple use the term “rolled edge” to mean a wire edge — that is, an edge that is not an edge at all, but a burr that’s been turned down. A wire edge will be razor-sharp but will break off and leave your knife dull the first time you use it. When used this way, “rolled edge” is a bad thing.

So when you hear the words “rolled edge”, you’ll need to lis­ten care­ful­ly to the con­text. If the speak­er is using the term approv­ing­ly, a con­vex edge is meant; if the speak­er is using the term dis­ap­prov­ing­ly, a wire edge is meant.

- The Chisel-ground Edge

Phil Harts­field has for years been mak­ing tan­tos with a chis­el grind, but Ernest Emer­son­’s CQC‑6 design and Bench­made’s Emer­son-designed 970 have real­ly pop­u­lar­ized the grind. Typ­i­cal­ly, the blade is an Amer­i­can­ized tan­to for­mat that’s ground on one side only (the oth­er side comes straight down). An edge bev­el is ground from the mid­dle of the blade and goes all the way through the edge. It is extreme­ly sharp.

The chis­el ground edge owes it sharp­ness to the fact that the edge bev­el is typ­i­cal­ly ground at around 30 degrees. Since the oppo­site side of the blade is essen­tial­ly at 0 degrees (it comes straight down with no bev­el), that’s a total of 30 degrees + 0 degrees = 30 degrees edge angle. With a more tra­di­tion­al edge, you’ll typ­i­cal­ly have each bev­el being ground at around 20 degrees, so that’s 20 degrees + 20 degrees = 40 degrees total edge angle.

To sharp­en the chis­el-ground edge, you’ll place the entire edge bev­el on the stone and grind it until a burr is formed. Many peo­ple then strop the edge on a piece of card­board on the oth­er side, to remove the burr. Option­al­ly, you can lay the flat side *flat* on a fine stone and do a lit­tle grind­ing from that side as well (some­thing guar­an­teed to mar the fin­ish). If you can’t bear to mar the fin­ish that way, lay the flat side as flat as you can — maybe 5‑degrees off the stone at most. What is crit­i­cal­ly impor­tant is to not grind a big sec­ond angle into the back (flat side) of the blade. The chis­el grind’s sharp­ness aris­es from the acute angle formed between the front bev­el and the flat back. You can then try to use decreas­ing pres­sure to grind off the burr, and fin­ish­ing with steel pro­vides real­ly nice results.

Harts­field and many oth­ers believe that for a right-hand­ed user, the edge bev­el should be on the right side of the knife (that is, the side that faces you when the knife tip is point­ing to the right). Fol­low­ing Emer­son­’s lead, most mak­ers are grind­ing the left side of the knife instead, appar­ent­ly because that’s where the mak­er’s stamp is tra­di­tion­al­ly posi­tioned, and adver­tise­ments look bet­ter if the stamp and edge are on the same side.

To see why the grind should be on the right side for a righty, think about try­ing to make a pre­cise cut in, say, a car­rot, or a piece of mate­r­i­al, or what­ev­er. If you’re like most right­ies, you want to hold the work in your left hand and cut with your right hand. If the knife is ground on the right side, then the flat part of the blade is the part you can see, and you can make sure the flat part of the blade is exact­ly along the line you want to cut. If the grind is on the left
side, the mate­r­i­al is div­ing under­neath the bev­el, and it’s dif­fi­cult to eye­ball whether or not you’re cut­ting in the right place. This adds to the chis­el-ground tan­to for­mat’s exist­ing prob­lems:

1) no bel­ly, and as such not the best gen­er­al util­i­ty for­mat, and

2) unsym­met­ri­cal grind, mak­ing pre­cise cut­ting dif­fi­cult.

The most pop­u­lar chis­el-ground fold­er, the Bench­made 97x series, uses a 30-degree sec­ondary grind to form the edge [Note: Bench­made uses a sec­ondary bev­el; most cus­tom mak­ers bring the pri­ma­ry bev­el all the way down to the edge]. The Lan­sky sys­tem includes a 30-degree posi­tion, but for some rea­son most users have found that the angle is not quite right (it’s unclear at this time whether it’s Lan­sky or Bench­made whose angle is not pre­cise­ly 30 degress). Some Lan­sky users on rec. knives has fash­ioned an exten­sion to the Lan­sky sys­tem to get the prop­er grind angle for the 97x, by extend­ing the post using
plas­tic from a milk car­ton. The Edge Pro, a sim­i­lar but much more expen­sive sys­tem, will get the 97x’s angle prop­er­ly.

V. Overview of Sharpening Systems

The first three sys­tems dis­cussed below all give out­stand­ing results, if the enthu­si­asm of rec.knives peo­ple is any indi­ca­tion. Some oth­er meth­ods of sharp­en­ing are dis­cussed in the mis­cel­la­neous sec­tion. The last sec­tion dis­cuss­es the advan­tages of free­hand sharp­en­ing, and why it’s worth attain­ing this skill even if you’re hap­py with what­ev­er sys­tem you have.

- Clamp-on sharpening guides (Razor Edge, Buck, etc.)

The clamp-on guide fas­tens to knife blade itself. It is used in con­junc­tion with a stan­dard stone (arkansas stone, dia­mond stone, syn­thet­ic stone, etc.). It is used with the exact same tech­niques as you would use to sharp­en free­hand, the guide mak­ing sure that all your angles are held per­fect­ly. If the blade has a bel­ly, the guide should be posi­tioned in the right place in order to keep a con­sis­tent angle through the entire edge grind; the instruc­tion book­let should
illus­trate that.

The most pop­u­lar clamp-on guide is the Razor Edge guide. I’ve already told you that the Razor Edge sharp­en­ing book is indis­pen­si­ble, but it’s espe­cial­ly impor­tant if you decide to use this sys­tem. Actu­al­ly, on top of that, buy the Razor Edge video as well. It is a huge advan­tage to actu­al­ly see some­one on video apply­ing the tech­niques, and I can’t rec­om­mend the video high­ly enough.

An advan­tage of this sys­tem is that because you are using the exact same motions as you would dur­ing free­hand sharp­en­ing, prop­er motion is put into mus­cle mem­o­ry. After sev­er­al months of using this sys­tem, I found that even the mechan­i­cal­ly-inept (like myself) could do a good job sharp­en­ing free­hand. See below for the advan­tages of free­hand sharp­en­ing.

The dis­ad­van­tage of this sys­tem is that one nev­er knows at what angle they are sharp­en­ing. For most of us, know­ing the exact sharp­en­ing angle prob­a­bly isn’t an issue.

- Clamp-and-Rod rigs (Lansky, Gatco, DMT, etc.)

Very pop­u­lar are the Lan­sky-type clamp-and-rod rigs. The knife is held in a clamp, and the back of the clamp pro­trudes upwards and has a num­ber of holes in it. The hone is attached to a rod. By putting the rod through one of the holes in the clamp, you can con­trol the sharp­en­ing angle you’re using. Most of these sys­tems have around 5 holes, cor­re­spond­ing to 5 dif­fer­ent grind angles. Dou­ble-grind­ing your edge should be very easy with this sys­tem.

One thing to watch out for is that sim­ple geom­e­try will tell you that as you sharp­en parts of the knife that are fur­ther from the clamp­ing point, the angle of sharp­en­ing will change. To sharp­en a very long knife, you may need to unclamp it and move it sev­er­al times dur­ing sharp­en­ing. The sys­tem works extreme­ly well for short knives, how­ev­er.

A num­ber of hones are sup­plied, cor­re­spond­ing to dif­fer­ent grits. Flat hones are used for plain blades. Some rigs have a tri­an­gu­lar hone avail­able to sharp­en ser­rat­ed blades.

The Edge Pro Apex sys­tem is rough­ly this type of sys­tem, but is of high­er qual­i­ty and price (retail­ing around $125). It also pro­vides greater angle gran­u­lar­i­ty than the rest. Although the price seems high, you should seri­ous­ly con­sid­er this sys­tem. By all reports, the qual­i­ty of the sys­tem is up to the price, it is very accu­rate, no mul­ti­ple re-clamp­ings need to be done.

- V‑type sharpeners (Spyderco Triangle, etc.)

Typ­i­cal­ly the V‑type sharp­en­ers have ceram­ic sticks stuck into a plas­tic base at a pre­set angle. The knife is held per­pen­dic­u­lar to the ground (a posi­tion which most peo­ple seem to be able to do eas­i­ly), and ground down the side of the sharp­en­er. The sys­tem is easy to use, but obvi­ous­ly, the angle is pre­set. If you want to use a dif­fer­ent angle, you’re out of luck. If your knife’s edge has been ground at a dif­fer­ent angle than the V, the first time you sharp­en it
the new angle will be ground in.

Dif­fer­ent ceram­ic sticks are sup­plied cor­re­spond­ing to dif­fer­ent grits. One Spy­der­co Tri-angle sharp­mak­er mod­el also has dia­mond sleeves that fit over the sticks and func­tion as a coars­er hone.

- Other miscellaneous

A num­ber of ceram­ic or dia­mond-coat­ed sticks are avail­able. They are often mar­ket­ed as steels, but since they remove met­al they do not actu­al­ly func­tion any­thing like prop­er steel, and should be con­sid­ered sharp­en­ers instead. Since there’s obvi­ous­ly no angle guide of any kind, some skill is need­ed to keep the angle con­sis­tent. If you’ve got the skill, these sticks work just fine.

There are a num­ber of gad­gets with pre-posi­tioned round “hones” (like Accusharp) that meet to form a V. You draw the knife straight through the sharp­en­ing mech­a­nism. Your knife will come out sharp­er, but some believe that repeat­ed use of these prod­ucts will harm the edge, as they often work by chip­ping out the edge. If that’s true, your knife will be hurt in the long run. In addi­tion, because no relief is ground into the blade each time, it will grad­u­al­ly become hard­er and hard­er to sharp­en your edge with these gad­gets, until final­ly you must spend some time on a bench­stone thin­ning the edge back out prop­er­ly.

There are elec­tric sharp­en­ing machines that have a rotat­ing stone, some­times in a water bath. They sup­pos­ed­ly work fine. Be *very* care­ful, how­ev­er. With some steels, it is very easy to heat up the steel and ruin the tem­per of the blade on these elec­tric machines, even in the cold water bath. Pull the blade off the machine and check it for warmth fre­quent­ly. In addi­tion, these machines can remove met­al very fast. It’s easy to sharp­en your knife away.

- Freehand sharpening, and its wondrous advantages!

Sharp­en­ing free­hand has some advan­tages to it, pro­vid­ed you have the skill to actu­al­ly get a sat­is­fac­to­ry edge. Per­haps the best advan­tage is that you don’t have to go hunt­ing around for hex keys, screws, nuts, or any oth­er lit­tle thing that might get lost from your sharp­en­ing rig. Nor do you need to waste time clamp­ing, screw­ing, and bolt­ing your knife into var­i­ous rigs. If your knife just needs a quick touch-up, swipe it on a stone and you’re done.

More impor­tant­ly, if you’re doing some­thing where weight becomes an issue (back­pack­ing, etc.), you prob­a­bly aren’t going to want to lug around your sharp­en­ing rig. I go out into the back­coun­try with my knife and a small light­weight 3“x1” dia­mond hone, con­fi­dent that I can use my knife hard and touch it up no prob­lem.

Last­ly, there’s a cer­tain sat­is­fac­tion in attain­ing the skill to sharp­en a knife hair-fling­ing sharp, espe­cial­ly when pre­vi­ous­ly your sharp­en­ing efforts seemed to make the knife duller!

Hap­py sharp­en­ing!

Joe Tal­madge


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